The present invention relates to sanitary napkins or menstruation pads for absorption and containment of body exudates.
Japanese Patent Application (PCT) Disclosure Gazette No. Hei6-502336 discloses a sanitary napkin comprising a liquid-pervious topsheet, a liquid-impervious backsheet, a liquid-absorbent core and spacer means functioning to maintain the topsheet spaced from the core. The napkin of such arrangement is maintained at a predetermined position relative to a wearer""s body even when an undergarment worn by the wearer of the napkin can not properly follow a movement of the weaver.
The spacer means of the above mentioned napkin is provided between the topsheet and the core and comprises tube or roll means through which body exudates should pass before absorbed by the core. Such manner of absorption is disadvantageous from the viewpoint of a rapidity and not suitable for the case in which a large amount of body exudates occurs at once.
In view of the problem as has been described above, it is an object of the present invention to provide a sanitary napkin improved so that the napkin can properly follow a movement of the wearer and rapidly absorb menstrual discharge.
According to the present invention, there is provided a sanitary napkin having a longitudinal direction and a transverse direction being orthogonal to the longitudinal direction, the napkin comprising a liquid-pervious topsheet, a back side member at least including a liquid-impervious sheet and a liquid-absorbent core disposed between the topsheet and the back side member, wherein:
the core presents, at a middle region of the longitudinal direction, an inverted V-shaped cross-section; the topsheet is placed upon an upper surface of the core while the core is lined by a shape-retaining panel having, in the transverse direction, a rigidity higher than that of the core and presenting an inverted V-shaped cross-section of a V-angle substantially identical to that of the core; the back side member extends outwards horizontally beyond transversely opposite side edges of the inverted V-shaped cross-section presented by the core; the topsheet is bonded to the upper surface of the back side member in regions thereof extending outwards beyond the side edges of the core; and the cross-section defines a substantially triangular space.
According to one embodiment of the invention, the back side member comprises a liquid-impervious plastic film.
According to another embodiment of the present invention, the back side member comprises a liquid-pervious sheet, a liquid-impervious sheet and a liquid-absorbent core disposed therebetween so that the liquid-pervious sheet and the liquid-impervious sheet define upper and lower surfaces of the back side member, respectively.
According to still another embodiment of the present invention, in the transverse direction of the napkin, the topsheet forms a pair of side flaps obliquely outwards and upwards extending beyond regions along which the topsheet is bonded to the back side member and the side flaps are provided in the vicinity of their ridges with elastic members extending in the longitudinal direction and bonded under tension to the respective side flaps so that the sanitary napkin presents a substantially W-shaped cross-section.
According to yet another embodiment of the present invention, the back side member is provided on its lower surface with adhesive fastener means used to fasten the napkin to an undergarment worn by the wearer of the napkin.
According to further additional embodiment of the present invention, the shape-retaining panel is made of a resilient material.